fix(inbox): show sent mail in the unified inbox + fix compose attach button

- inbox merges crm.mail.list threads (kind MAIL) into crm.inbox.list items so
  sent/received mail actually appears in the one surface; mail shows in the
  Open view (it has no inbox work-item state) and opens in MailReader on click.
  Mail rows are read/reply only — no Done/Snooze/Archive (crm.inbox.transition
  doesn't apply to a mail thread).
- compose Attachments block was wrapped in <Field> (a <label>), so the label
  hijacked the Attach button's click via label→file-input association and the
  picker misfired. Use a plain div with the same field styling.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/components/dashboard/mail.tsx

@@ -216,13 +216,16 @@ export function NewMailModal({ open, onClose, onSent, onError }: { open: boolean
       <Field label="Subject"><input value={subject} onChange={(e) => setSubject(e.target.value)} placeholder="Subject" style={inputStyle} /></Field>
       <Field label="Message"><textarea value={body} onChange={(e) => setBody(e.target.value)} placeholder="Write your message…" rows={6} style={{ ...inputStyle, resize: "vertical" }} /></Field>
 
-      <Field label="Attachments">
+      {/* NOT a <Field> (which is a <label>): a label wrapping the file input would hijack the
+          Attach button's click via label→input association and open the picker erratically. */}
+      <div className="ds-field">
+        <span className="ds-field-lbl">Attachments</span>
         <input ref={fileRef} type="file" multiple style={{ display: "none" }} onChange={onPickFile} />
         <div style={{ display: "flex", flexWrap: "wrap", gap: 8, alignItems: "center" }}>
           <Btn variant="outline" icon="paperclip" onClick={() => fileRef.current?.click()} disabled={uploading || staged.length >= 10}>{uploading ? "Uploading…" : "Attach"}</Btn>
           {staged.map((f, i) => <StagedChip key={`${f.contentRef}_${i}`} file={f} onRemove={() => setStaged((s) => s.filter((_, j) => j !== i))} />)}
         </div>
-      </Field>
+      </div>
     </Modal>
   );
 }